2017-09-15 07:29 AM
Hi All,
I am using STM32l073 nucleo board with module. I am unable to get power more than 14.6 dBm while transmitting data packet. On my other device i am able to get 19 dbm of power using same sx1272 module.
I tried writing the PADAC and PACONFIG registers separately as well still my power is not going above 14.6 dBm.
Any help would be greatly appreciated
Thanks
#nucleo-l073rz #lora #sx12722017-09-15 08:24 AM
Are these 'modules' of the same design? What's the tolerance of the parts in the RF path?
Can't fix hardware issues with more software..
Your description doesn't have the details I need to see if we're talking about an apples-to-apples comparison.
Custom modules, data sheets, images, links to...
This?
http://www.st.com/en/evaluation-tools/p-nucleo-lrwan1.html
2017-09-18 04:02 AM
Hi,
I am using P-NUCLEO-LRWAN1 for Indian ISM band (ISM_865), As per Indian ISM band maximum radiated power is 30dBm but i am not getting more than 14dBm.
Software Details: en.i-cube_lrwan (downloaded from Stmicroeletronics site)
Define Indian Region (REGION_IN865) in preprocessor directive
I know Sx1272 is capable to radiate till 20dBm only.
Question: Is there any setting to get more than 14 dBm output, any hardware dependency or power (5 v , 12 v)?
I am using USB port for power
Any help would be greatly appreciated
Thanks
2017-09-18 08:22 AM
,
,
Measuring at the output or via software settings?
♯ define TX_OUTPUT_POWER , , , , , , , , , , , , , , , , , , , , , , , , , , , , 20 , , , , , , , // dBm (14 - 25mW, 20 - 100mW)
Not aware of any supply side issues, USB should be able to supply sufficient current for 100mW operation. You could try a 2.1A type USB charger supply.
Have you reviewed the schematic for the shield?
2017-09-19 12:28 AM
I tried changing this but had the same result. I also tried to writing into the PACONFIG register directly which provides the 20db boost but to no avail.
2017-09-20 12:44 AM
I tried changing
#define TX_OUTPUT_POWER 20 // dBm (14 - 25mW, 20 - 100mW) on
en.i-cube_lrwan ping_pong project Indian ISM band
but had the same result ,Measuring at the output on Spectrum analyzer getting 14dbm still now.this is my
en.i-cube_lrwan End_node project min ,max and default powers.
/*!
* Minimal Tx output power that can be used by the node */#define IN865_MIN_TX_POWER TX_POWER_10/*!
* Maximal Tx output power that can be used by the node */#define IN865_MAX_TX_POWER TX_POWER_0/*!
* Default Tx output power used by the node */#define IN865_DEFAULT_TX_POWER TX_POWER_0/*! * Default Max EIRP */#define IN865_DEFAULT_MAX_EIRP 30.0f/*! * Default antenna gain */#define IN865_DEFAULT_ANTENNA_GAIN 2.15fany idea how to get max tx_power of 20dbm please guide me.
2017-09-20 07:35 PM
Have you tried a 915 MHz signal?
Have you checked the current limiter settings?
2017-12-07 08:57 AM
Must also adjust the current limit settings in SX1272
2017-12-07 03:35 PM
By default, the LoRaWAN EndNode example has Adaptive Data Rate (ADR) defined - you need to turn that off.
See my earlier question:
https://community.st.com/0D50X00009XkbSMSAZ
As far as I can find, there is no proper API to specify the output power.
:(
EDIT
Just to say that I was only looking to reduce output power - didn't investigate how to increase it!